Low idle

suprabahamut · 12-30-2009, 09:42 PM

My idle is low when the car warms up. I am thinking it is the IAC valve. I shot some carburetor cleaner in the valve with the hose disconnected. A lot of junk cam out, but it is still idling low and sometimes surges till it cuts off it kind of ticks when it gets really low idle like 500 rpms. What do you guys think do you think it is the IAC or something else?

cre · 12-31-2009, 06:09 AM

Well, the ISCV is VERY easy to clean thoroughly, but just spraying carb cleaner through it won't necessarily reach where it needs to; Take the ISCV off and then take off the three screws, clean the area above the plunger and then lubricate it with a good lube... a molybdenum based grease will work well, but a dry teflon lube may collect less grime over time.

There are a few possibilities with any idle issue... I HATE idle issues, so I just go through a check list whether it's high or low:

1) check for vacuum leaks
2) check ISCV
3) check calibration of TPS
4) test TPS for flat spots (it is a wear component)
5) test TCCS temp sensor
6) test VAFM for flat spots

Oh, and as always, check for codes.

12-30-2009, 09:42 PM	#1
suprabahamut 3" Exhaust Join Date: May 2007 Location: greensboro Posts: 242	Low idle My idle is low when the car warms up. I am thinking it is the IAC valve. I shot some carburetor cleaner in the valve with the hose disconnected. A lot of junk cam out, but it is still idling low and sometimes surges till it cuts off it kind of ticks when it gets really low idle like 500 rpms. What do you guys think do you think it is the IAC or something else?

12-31-2009, 06:09 AM	#2
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	Well, the ISCV is VERY easy to clean thoroughly, but just spraying carb cleaner through it won't necessarily reach where it needs to; Take the ISCV off and then take off the three screws, clean the area above the plunger and then lubricate it with a good lube... a molybdenum based grease will work well, but a dry teflon lube may collect less grime over time. There are a few possibilities with any idle issue... I HATE idle issues, so I just go through a check list whether it's high or low: 1) check for vacuum leaks 2) check ISCV 3) check calibration of TPS 4) test TPS for flat spots (it is a wear component) 5) test TCCS temp sensor 6) test VAFM for flat spots Oh, and as always, check for codes. __________________ If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum. If you're so inclined I'm always more than happy to accept tips via PayPal. Tip Jar --->

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